TheTokina TM16Z7518GAIDCPN is specifically designed for these purposes. Through the use of a compatible CCTV lens controller device, you'll be able to actively change the focal length on the lens from a wide view of 7.5mm to a telephoto view of 120mm, which translates into a 16x optical zoom. And with a name like Tokina, you can expect to get only the best, both in terms of image quality and lens durability.